Spectral (or color) measurement is required in many industries or businesses that produce, use, or sell dyes, inks, paints, and other color products. Color measurement has also become increasingly involved in consumer products. For example, many test products used in laboratories or households for conducting chemical or biochemical analyses display the test results by way of color, as evaluated by eyes or by color measuring devices. In many applications, it is desirable to have spectral (or color) measuring devices that are compact in size (e.g., handheld), accurate in color determination, and economical in cost.
Conventional spectral measuring devices employ diffraction gratings and associated optical elements to detect the spectral responses (or colors) of a test object. As a result, such devices are characteristically expensive and bulky, rendering them unsuitable as consumer products. Although relatively inexpensive and lightweight devices for color measurement have become available in recent years, which make use of light emitting diodes (LEDs) for illumination and optical sensors for detection, these devices suffer a number of limitations, notably unsatisfactory accuracy in color determination.
In view of the forgoing, a need therefore exists in the art, for spectral measuring devices that overcome the aforementioned limitations.